By any chance, are lip fillers effective for increasing the width as well?

Hello! I've been considering lip fillers lately. It's partly because full lips are in style, but also because my lips are quite narrow—should I call them small or short? Because of that, they sometimes look a bit puffy. I've always been really envious of people with wide, open lips that look pretty when they smile. I'm wondering if lip fillers can actually be effective for increasing the width of the mouth. Since lip fillers are usually intended to make lips thicker, I assume they tend to lengthen the vertical length, but I'm curious if there is a separate procedure specifically effective for increasing the horizontal length. I really want to get rid of these tight-looking lips... Has anyone else had similar concerns and gotten filler treatments? Did you see any results?